Release device, particularly for switches or similar, of small power

ABSTRACT

An electric switch in which the movable contact-carrier is in the form of a rockable lever, the ends of which are engaged by the ends of an arcuated leaf spring depressed by a U-shaped member. This rockable lever is operated by a rockable operating member which is provided with two parallel depending projections, embracing the U-shaped member and the movable contact-carrier.

United States Patent Bonetalli 51 May 9, 1972 [54] RELEASE DEVICE, PARTICULARLY FOR SWITCHES OR SIMILAR, OF

SMALL POWER [72] Inventor: Angelo Bonetalli, Via Lazio 39, Varese,

Italy [22] Filed: Nov. 12, 1970 211 Appl. No.: 88,766

[30] Foreign Application Priority Data Nov. 29, 1969 Italy ..25l27 A/69 [52] US. Cl. ..200/67 G [51] Int. Cl. ....H0lh 13/28 [58] Field of Search ..200/67 G, 68

[56] References Cited FOREIGN PATENTS OR APPLICATIONS 1,206,645 8/l959 France 200/67 G 775,693 H1968 Canada ..200/67 G 1,085,096 9/1967 Great Britain .....200/67 G Primary Examiner-David Smith, Jr. Attorney-Michael S. Striker ABSTRACT An electric switch in which the movable contact-carrier is in the form of a rockable lever, the ends of which are engaged by the ends of an arcuated leaf spring depressed by a U-shaped member. This rockable lever is operated by a rockable operating member which is provided with two parallel depending projections, embracing the U-shaped member and the movable contact-carrier.

10 Claims, 1 Drawing Figure PATENTEBMM 91972 MM N Jm/yh a a1 a A M RELEASE DEVICE, PARTICULARLY FOR SWITCHES OR SIMILAR, OF SMALL POWER This invention relates to electric switches, particularly electric switches for small powers.

According to the present invention there is provided an electric switch comprising an arm mounted on a fulcrum so as to be rockable between two positions in which movable contacts carried by the arm are selectively engaged with corresponding fixed contacts, a leaf spring secured to the arm, a rockable operating member having a pair of projections which extend one on each side of said fulcrum, and a generally U- shaped member the outer end portions of which respectively engage said projections, and the transverse portion of which engages the leaf spring, whereby rocking of the operating member varies the force of said transverse portion on the leaf spring with consequent reversal of the position of the arm.

Preferably the leaf spring is of generally semi-circular shape, but with the central region curved in the opposite sense to provide a surface which is concave outwards and with which said transverse portion engages, the ends of the leaf spring being secured to respective ends of the arm.

An electric switch in accordance with the present invention will now be described by way of example with reference to the accompanying drawing, which shows a cross-section through the switch.

Referring to the drawing, the switch comprises an arm 1 carrying movable contacts 2 and 3, and rockable on a fulcrum 4 between two position. In the two positions the movable contacts 2 and 3 selectively engage stationary contacts 2' and 3' respectively.

The ends of a leaf spring 5 of generally semi-circular shape are secured to respective ends of the arm 1 so that the deformable leaf spring 5 is disposed on the opposite side of the arm 1 to the movable contacts 2 and 3. The leaf spring 5, in the shape of a saddle is compressed towards the arm 1 by an engaging means or a generally U-shaped bridge member 6, the transverse portion 7 of which engages the central region of the leaf spring 5, which region is curved in the opposite sense to provide a bearing portion or a surface which is concave outwards. The outer end portions of the bridge member 6 engage in respective recesses 8 formed in the ends of projections 9 formed on an operating rocker member 10. The projections or extensions 9 extend one on each side of the fulcrum 4.

The operating member 10 is of known form, and it can rock about an axis within arcuate recess 12 into which a rounded projection 13 extending from each projection 9 engages, and the apex of which is formed by a small collar 14, which encircles the switch casing.

As shown in the drawing, the bridge member 6 moves when the operating member 10 is rocked, and thereby varies the force on the leaf spring 5 such that the position of the arm 1 is reversed. It is to be noted, however, that during initial movement of the bridge member 6 the leaf spring 5 is deformed without the arm 1 moving, but when this deformation exceeds a certain amount the arm 1 snaps over to reverse the engagement of the contacts 2 and 2, and 3 and 3'. Moreover the leaf spring 5 acts to reduce contact bounce.

Various modifications can of course be made without departing from the scope of the invention as defined by the appended claims.

What we claim is:

1. An electric switch comprising a stationary portion; fulcrum means fixed relative to said stationary portion; and arm pivotable on said fulcrum means between two positions relative to said stationary portion and having opposite surfaces; at least one pair of contacts, respectively mounted on said stationary portion and said arm, said contacts becoming closed in one of said positions of said arm; deformable spring means extending in a direction longitudinal of said arm and spaced from one surface thereof for snapping said arm from one position to the other position in response to forces applied to said spring means which deform and urge a bearing portion of said spring means in a direction transversely of said fulcrum means; an operating rocker member mounted on said stationary portion, said rocker member having at least one extension which has an end portion projecting beyond the other surface of said arm, said end portion being movable to either side of said fulcrum means during rocking of said rocker member; and engaging means engaging said extension and said spring means for deforming and urging said bearing portion of said spring means in said transverse direction in order to effect the snapping action.

2. An electric switch as defined in claim 1, wherein said arm has two ends, each end being positioned at another side of said fulcrum means, and wherein said switch comprises two pairs of contacts, each pair being located at another end of said arm and respectively mounted on said stationary portion and said arm, whereby one pair of contacts becomes closed in each of said two positions of said arm.

3. An electric switch as defined in claim 1, wherein said arm has a pivoting portion adapted to pivot said arm on said fulcrum means, said spring means comprising a saddle-shaped spn'ng secured at opposite ends of said pivoting portion.

4. An electric switch as defined in claim 3, wherein said spring is a leaf spring.

5. An electric switch as defined in claim 1, wherein said rocker member has a rocking axis, said extension end portion and said rocking axis being located on opposite sides of said arm.

6. An electric switch as defined in claim 1, wherein said extension end portion has a recess and wherein said engaging means comprises a rigid member having a pair of portions one of which engages said bearing portion and the other of which is located in said recess.

7. An electric switch as defined in claim 6, wherein said rigid member is movable in said recess during rocking of said rocking member.

8. An electric switch as defined in claim 6, wherein said operating rocker member has two extensions, one on each side of said spring means, said rigid member being U-shaped, forming said engaging means and consisting of a transverse portion and two legs attached to the latter, each leg having fixed thereon end portions which extend in directions substantially parallel to said transverse portion, said transverse portion being in contact with said bearing portion and said end portions respectively being engaged with said extensions.

9. An electric switch as defined in claim 1, wherein the rocking axis of said rocker member is located intermediate of said bearing portion and said extension end portion.

10. An electric switch as defined in claim 1, wherein the rocking axis of said rocking member and the fulcrum point of said fulcrum means define a plane, said bearing portion being movable to one side of the plane in response to movement of said extension end portion to said one side of the plane, said engaging means maintaining said end portion and said bearing portion in substantially fixed spaced relation to each other in opposition to the action of said spring means. 

1. An electric switch comprising a stationary portion; fulcrum means fixed relative to said stationary portion; and arm pivotable on said fulcrum means between two positions relative to said stationary portion and having opposite surfaces; at least one pair of contacts, respectively mounted on said stationary portion and said arm, said contacts becoming closed in one of said positions of said arm; deformable spring means extending in a direction longitudinal of said arm and spaced from one surface thereof for snapping said arm from one position to the other position in response to forces applied to said spring means which deform and urge a bearing portion of said spring means in a direction transversely of said fulcrum means; an operating rocker member mounted on said stationary portion, said rocker member having at least one extension which has an end portion projecting beyond the other surface of said arm, said end portion being movable to either side of said fulcrum means during rocking of said rocker member; and engaging means engaging said extension and said spring means for deforming and urging said bearing portion of said spring means in said transverse direction in order to effect the snapping action.
 2. An electric switch as defined in claim 1, wherein said arm has two ends, each end being positioned at another side of said fulcrum means, and wherein said switch comprises two pairs of contacts, each pair being located at another end of said arm and respectively mounted on said stationary portion and said arm, whereby one pair of contacts becomes closed in each of said two positions of said arm.
 3. An electric switch as defined in claim 1, wherein said arm has a pivoting portion adapted to pivot said arm on said fulcrum means, said spring means comprising a saddle-shaped spring secured at opposite ends of said pivoting portion.
 4. An electric switch as defined in claim 3, wherein said spring is a leaf spring.
 5. An electric switch as defined in claim 1, wherein said rocker member has a rocking axis, said extension end portion and said rocking axis being located on opposite sides of said arm.
 6. An electric switch as defined in claim 1, wherein said extension end portion has a recess and wherein said engaging means comprises a rigid member having a pair of portions one of which engages said bearing portion and the other of which is located in said recess.
 7. An electric switch as defined in claim 6, wherein said rigid member is movable in said recess during rocking of said rocking member.
 8. An electric switch as defined in claim 6, wherein said operating rocker member has two extensions, one on each side of said spring means, said rigid member being U-shaped, forming said engaging means and consisting of a transverse portion and two legs attached to the latter, each leg having fixed thereon end portions which extend in directions substantially parallel to said transverse portion, said transverse portion being in contact with said bearing portion and said end portions respectively being engaged with said extensions.
 9. An electric switch as defined in claim 1, wherein the rocking axis of said rocker member is located intermediate of said bearing portion and said extension end portion.
 10. An electric switch as defined in claim 1, wherein the rocking axis of said rocking member and the fulcrum point of said fulcrum means define a plane, said bearing portion being movable to one side of the plane in response to movement of said extension end portion to said one side of the plane, said engaging means maintaining said end portion and said bearing portion in substantially fixed spaced relation to each other in opposition to the action of said spring means. 